/*! \file bcmcnet_intr.c
 *
 * Utility routines for BCMCNET interrupt processing.
 */
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#include <bcmcnet/bcmcnet_main.h>
#include <bcmcnet/bcmcnet_core.h>
#include "bcmcnet_intr.h"

static struct pdma_intr_ctrl intr_ctrl[NUM_PDMA_DEV_MAX];

/*!
 * Interrupt handling thread
 */
static void
bcmcnet_intr_process(void *vp)
{
    struct pdma_dev *dev = vp;
    struct pdma_intr_ctrl *intr = &intr_ctrl[dev->unit];
    struct pdma_intr_source *src = NULL;
    int qi;

    while (!intr->abort) {
        sal_sem_take(intr->sem, SAL_SEM_FOREVER);

        /* Handle all the active interrupts */
        do {
            for (qi = 0; qi < dev->num_queues; qi++) {
                src = &intr->intr_src[qi];

                sal_spinlock_lock(src->lock);
                intr->poll_active &= ~(1 << qi);
                if (src->active && src->enabled && src->intr_cb) {
                    intr->poll_active |= 1 << qi;
                    sal_spinlock_unlock(src->lock);

                    /* Call actual callback */
                    src->intr_cb(src->intr_hdl, src->intr_ck);
                } else {
                    sal_spinlock_unlock(src->lock);
                }
            }
        } while (intr->poll_active);
    }

    for (qi = 0; qi < dev->num_queues; qi++) {
        src = &intr->intr_src[qi];
        src->active = 0;
        src->enabled = 0;
    }

    intr->poll_active = 0;
    intr->pid = SAL_THREAD_ERROR;

    sal_thread_exit(0);
}

/*!
 * Initialize interrupt handling
 */
int
bcmcnet_intr_ctrl_init(struct pdma_dev *dev)
{
    struct pdma_intr_ctrl *intr = &intr_ctrl[dev->unit];
    struct pdma_intr_source *src = NULL;
    int qi;

    for (qi = 0; qi < dev->num_queues; qi++) {
        src = &intr->intr_src[qi];
        src->lock = sal_spinlock_create("intr_source_lock");
        if (!src->lock) {
            goto error;
        }
    }

    intr->sem = sal_sem_create("intr_ctrl_sem", SAL_SEM_BINARY, 0);
    if (!intr->sem) {
        goto error;
    }

    /* Create the helper thread to handle the interrupt */
    intr->abort = 0;
    intr->pid = sal_thread_create(dev->name, SAL_THREAD_STKSZ,
                                  SAL_THREAD_PRIO_DEFAULT,
                                  bcmcnet_intr_process, (void *)dev);
    if (intr->pid == SAL_THREAD_ERROR) {
        CNET_PR("Could not start interrupt thread for device %d\n", dev->unit);
        goto error;
    }

    return SHR_E_NONE;

error:
    if (intr->sem) {
        sal_sem_destroy(intr->sem);
        intr->sem = NULL;
    }

    for (qi = 0; qi < dev->num_queues; qi++) {
        src = &intr->intr_src[qi];
        if (src->lock) {
            sal_spinlock_destroy(src->lock);
            src->lock = NULL;
        }
    }

    return SHR_E_MEMORY;
}

/*!
 * De-initialize interrupt handling
 */
int
bcmcnet_intr_ctrl_deinit(struct pdma_dev *dev)
{
    struct pdma_intr_ctrl *intr = &intr_ctrl[dev->unit];
    struct pdma_intr_source *src = NULL;
    int qi;
    int retry = 1000;
    int rv = SHR_E_NONE;

    if (intr->pid && intr->pid != SAL_THREAD_ERROR) {
        intr->abort = 1;
        sal_sem_give(intr->sem);

        while (intr->pid != SAL_THREAD_ERROR && retry--) {
            sal_usleep(1000);
        }
        if (intr->pid != SAL_THREAD_ERROR) {
            CNET_PR("Interrupt thread will not exit\n");
            rv = SHR_E_INTERNAL;
        }
    }

    if (intr->sem) {
        sal_sem_destroy(intr->sem);
        intr->sem = NULL;
    }

    for (qi = 0; qi < dev->num_queues; qi++) {
        src = &intr->intr_src[qi];
        src->intr_hdl = NULL;
        src->intr_cb = NULL;
        src->intr_ck = NULL;
        if (src->lock) {
            sal_spinlock_destroy(src->lock);
            src->lock = NULL;
        }
    }

    return rv;
}

/*!
 * Register the callback for the specific interrupt handle
 */
int
bcmcnet_intr_cb_register(struct intr_handle *hdl, pdma_intr_cb_t cb, void *ck)
{
    struct pdma_intr_ctrl *intr = NULL;
    struct pdma_intr_source *src = NULL;

    if (!hdl || !ck) {
        return SHR_E_PARAM;
    }

    intr = &intr_ctrl[hdl->unit];
    src = &intr->intr_src[hdl->chan];

    if (src->intr_cb || src->intr_ck) {
        return SHR_E_PARAM;
    }

    src->intr_hdl = hdl;
    src->intr_cb = cb;
    src->intr_ck = ck;

    return SHR_E_NONE;
}

/*!
 * Unregister the callback according to the specified interrupt handle
 */
int
bcmcnet_intr_cb_unregister(struct intr_handle *hdl, pdma_intr_cb_t cb, void *ck)
{
    struct pdma_intr_ctrl *intr = NULL;
    struct pdma_intr_source *src = NULL;

    if (!hdl || !ck) {
        return SHR_E_PARAM;
    }

    intr = &intr_ctrl[hdl->unit];
    src = &intr->intr_src[hdl->chan];
    if (src->intr_cb == cb && (ck == (void *)-1 || ck == src->intr_ck)) {
        src->intr_hdl = NULL;
        src->intr_cb = NULL;
        src->intr_ck = NULL;
    }

    return SHR_E_NONE;
}

/*!
 * Enable the poll processing for the specified handle
 */
void
bcmcnet_poll_enable(struct intr_handle *hdl)
{
    struct pdma_intr_ctrl *intr = &intr_ctrl[hdl->unit];
    struct pdma_intr_source *src = &intr->intr_src[hdl->chan];

    sal_spinlock_lock(src->lock);
    src->enabled = 1;
    sal_spinlock_unlock(src->lock);
}

/*!
 * Disable the poll processing for the specified handle
 */
void
bcmcnet_poll_disable(struct intr_handle *hdl)
{
    struct pdma_intr_ctrl *intr = &intr_ctrl[hdl->unit];
    struct pdma_intr_source *src = &intr->intr_src[hdl->chan];

    sal_spinlock_lock(src->lock);
    src->enabled = 0;
    sal_spinlock_unlock(src->lock);
}

/*!
 * Schedule the poll processing for the specified handle
 */
void
bcmcnet_poll_schedule(struct intr_handle *hdl)
{
    struct pdma_intr_ctrl *intr = &intr_ctrl[hdl->unit];
    struct pdma_intr_source *src = &intr->intr_src[hdl->chan];

    sal_spinlock_lock(src->lock);
    src->active = 1;
    sal_spinlock_unlock(src->lock);

    sal_sem_give(intr->sem);
}

/*!
 * Complete the poll processing for the specified handle
 */
void
bcmcnet_poll_complete(struct intr_handle *hdl)
{
    struct pdma_intr_ctrl *intr = &intr_ctrl[hdl->unit];
    struct pdma_intr_source *src = &intr->intr_src[hdl->chan];

    sal_spinlock_lock(src->lock);
    src->active = 0;
    sal_spinlock_unlock(src->lock);
}

/*!
 * Check the poll processing for the specified handle
 */
int
bcmcnet_poll_check(struct intr_handle *hdl)
{
    struct pdma_intr_ctrl *intr = &intr_ctrl[hdl->unit];
    struct pdma_intr_source *src = &intr->intr_src[hdl->chan];
    int polling;

    sal_spinlock_lock(src->lock);
    polling = !!(intr->poll_active & 1 << hdl->chan);
    sal_spinlock_unlock(src->lock);

    return polling;
}

